Slotted/drilled rotors are for show, period. The escaping gasses (green gassing) is really negligible. The slots/holes are just more prone to heat differences and thus crack easier there. For the roadcourse I would stay away from them, for the street they do look cool (but thats about it).
As for the duct shield, if you are on a roadcourse, then your should remove it and get some brake ducting in there. For the street, just leave it. The rain/dirt will not be worth it (you wont notice anything, barely).
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Darius Rudis
Roadracer: Home built t-arm/panhard suspension powered by an S-trimmed motor :-)
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